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1.
Sci Rep ; 14(1): 7491, 2024 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553576

RESUMO

The plants that we consume in our daily diet and use as a risk preventer against many diseases have many biological and pharmacological activities. In this study, the phytochemical fingerprint and biological activities of Beta vulgaris L. leaf extract, which are widely consumed in the Black Sea region, were investigated. The leaf parts of the plant were dried in an oven at 35 °C and then ground into powder. The main constituents in B. vulgaris were identified by LC-MS/MS and GC-MS analyses. Phenolic content, betaxanthin and betacyanin levels were investigated in the extracts obtained using three different solvents. The biological activity of the extract was investigated by anti-microbial, anti-mutagenic, anti-proliferative and anti-diabetic activity tests. Anti-diabetic activity was investigated by in vitro enzyme inhibition and in-silico molecular docking was performed to confirm this activity. In the LC-MS analysis of B. vulgaris extract, a major proportion of p_coumaric acid, vannilin, protecatechuic aldehyde and sesamol were detected, while the major essential oils determined by GC-MS analysis were hexahydrofarnesyl acetone and phytol. Among the solvents used, the highest extraction efficiency of 2.4% was obtained in methanol extraction, and 36.2 mg of GAE/g phenolic substance, 5.1 mg/L betacyanin and 4.05 mg/L betaxanthin were determined in the methanol extract. Beta vulgaris, which exhibited broad-spectrum anti-microbial activity by forming a zone of inhibition against all tested bacteria, exhibited anti-mutagenic activity in the range of 35.9-61.8% against various chromosomal abnormalities. Beta vulgaris extract, which did not exhibit mutagenic, sub-lethal or lethal effects, exhibited anti-proliferative activity by reducing proliferation in Allium root tip cells by 21.7%. 50 mg/mL B. vulgaris extract caused 58.9% and 55.9% inhibition of α-amylase and α-glucosidase activity, respectively. The interactions of coumaric acid, vanniline, hexahydrofarnesyl acetone and phytol, which are major compounds in phytochemical content, with α-amylase and α-glucosidase were investigated by in silico molecular docking and interactions between molecules via various amino acids were determined. Binding energies between the tested compounds and α-amylase were obtained in the range of - 4.3 kcal/mol and - 6.1 kcal/mol, while for α-glucosidase it was obtained in the range of - 3.7 kcal/mol and - 5.7 kcal/mol. The biological activities of B. vulgaris are closely related to the active compounds it contains, and therefore studies investigating the phytochemical contents of plants are very important. Safe and non-toxic plant extracts can help reduce the risk of various diseases, such as diabetes, and serve as an alternative or complement to current pharmaceutical practices.


Assuntos
Beta vulgaris , Diabetes Mellitus , Simulação de Acoplamento Molecular , Cromatografia Gasosa-Espectrometria de Massas , Metanol/química , Beta vulgaris/metabolismo , Cromatografia Líquida , Espectrometria de Massa com Cromatografia Líquida , Acetona/análise , Ácidos Cumáricos/análise , alfa-Glucosidases/metabolismo , Betacianinas , Betaxantinas , Espectrometria de Massas em Tandem , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Solventes/química , alfa-Amilases , Compostos Fitoquímicos/química , Fitol , Antioxidantes/farmacologia
2.
Chem Biodivers ; 20(8): e202300332, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37461844

RESUMO

The present study shows the chemical profile, antimicrobial, antiproliferative, and apoptotic effects of Stemodia viscosa extracts. Thirteen bioactive compounds were identified in the 80 % ethanolic extract by GC/MS analysis. The acetone extract exhibited a higher content of flavonoids and phenols of 805.10 µg QE/mg DW and 89.31 µg GAE/mg DW extracts, respectively. Furthermore, the acetone extract possessed the highest antioxidant activity (IC50 =9.96 µg/mL). The 80 % ethanolic extract exhibited significant antimicrobial activity; the highest activity was observed against Staphylococcus aureus with a zone of inhibition of 25±0.51 mm, MIC value of 4 mg/mL, and MBC value of 8 mg/mL. The antiproliferative results revealed the presence of anticancer activity with an IC50 =91.562 and 74.362 µg/mL against the B16F10 skin and COLO205 colon cancer cells, respectively. The flow cytometric analysis shows that the plant extracts cause cancer cell death through the induction of apoptosis. Our findings confirmed that Stemodia viscosa is a potential source of biologically active compounds.


Assuntos
Acetona , Anti-Infecciosos , Acetona/análise , Anti-Infecciosos/química , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/química , Cromatografia Gasosa-Espectrometria de Massas , Antioxidantes/química , Flavonoides/farmacologia
3.
Chem Biodivers ; 20(5): e202201051, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37032441

RESUMO

The stilbene-rich acetone fraction in high yield (6.6 %, PEAS) of Passiflora edulis Sims was prepared and evaluated for neuroprotective activity in murine Alzheimer's disease model induced by aluminum chloride and D-galactose. The phytochemical and HPLC-DAD-MS analysis of the polyphenolic stilbene-rich acetone fraction showed that it contained different stilbenes including trans-piceatannol, scirpusins A-B and cassigarol E. The total phenolic content (TPC) of PEAS was 413.87±1.71 mg GAE eqv/g. The neuroprotective activity of PEAS is typically presented in the Morris water maze-reference Spatial Memory test, where the Alzheimer's mice treated at 100 mg/kg (Alz-ED1) and 200 mg/kg (Alz-ED2) spent less than 47 % and 66 % of the time, respectively, than the Alzheimer's model mice (Alz). Two simple stilbenes, trans-piceatannol and trans-resveratrol, showed selectively inhibitory activity in silico against acetylcholinesterase (AChE). Two stilbene dimers, cassigarol E and scirpusin A, exhibited low nanomolar inhibitory potential against AChE and butyrylcholinesterase (BChE), significantly lower than those of the positive control, donepezil and tacrine. These findings suggest that the stilbenes from P. edulis seeds, particularly the stilbene dimers, warrant further investigation as potential neuroprotective candidates in the prevention of cognitive deficits associated with Alzheimer's disease.


Assuntos
Doença de Alzheimer , Passiflora , Estilbenos , Animais , Camundongos , Acetona/análise , Acetilcolinesterase/química , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Butirilcolinesterase/química , Inibidores da Colinesterase/farmacologia , Passiflora/química , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Extratos Vegetais/análise , Sementes/química , Estilbenos/farmacologia , Estilbenos/uso terapêutico
4.
J Sci Food Agric ; 103(10): 5138-5144, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36988948

RESUMO

BACKGROUND: Tomato seed oil (TSO) was obtained using a combined method of pre-keeping in solvent and Soxhlet extraction. A considerable oil yield could not be obtained using samples without drying or grinding, with dried or non-dried seeds, which were not kept in solvent (<2%). For this purpose, oil yield, physicochemical properties, oxidation values, spectrophotometric indices and fatty acid composition of the samples extracted with acetone, ethyl acetate, chloroform and petroleum ether were determined. RESULTS: Oils obtained by the extraction of petroleum ether (20.36 meq g O2 kg-1 ) and ethyl acetate (11.16 meq g O2 kg-1 ) were found to have very high peroxide values. Besides, a high-quality edible oil should have an anisidine value (p-AnV) of less than 10. Samples extracted with chloroform alone had a p-AnV of 8.86, while slightly higher values were found for other samples (P < 0.05). Chloroform (20.50) and acetone (23.06) both gave the best results and met the expected value, with total oxidation value below 30. Finally, the highest levels of primary fatty acids observed were linoleic acid (32.77-41.95%), palmitic acid (23.75-32.27%), oleic acid (16.17-24.52%), and stearic acid (7.76-12.82%). CONCLUSION: This process is applicable to recycling tomato sauce waste and essential oil. The research proved that the seed-drying process and pre-keeping in solvent have an important effect on oil yield, quality and fatty acid composition. © 2023 Society of Chemical Industry.


Assuntos
Solanum lycopersicum , Solventes/química , Acetona/análise , Clorofórmio/análise , Ácidos Graxos/química , Sementes/química , Óleos de Plantas/análise
5.
Appl Biochem Biotechnol ; 195(7): 4570-4582, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36705843

RESUMO

The objective of this study was to evaluate phytochemicals present in the resin of Garcinia indica (Gamboge). We assessed the phytochemical constituents and antioxidant potential of acetone, methanol, and water extracts of resin. Acetone and methanol extracts contain a high amount of phenolics (183.90 and 182.85 mg GAE (gallic acid equivalent)/g) and flavonoids (72.65 and 71.33 mg QE (quercetin equivalent)/g), respectively, whereas methanol extract had the highest 7.62 mg AE (atropine equivalent)/g of alkaloid. GC-MS analysis of acetone extract identified 15 compounds and the majority of them were terpenoids, and 9,19-cyclo-25,26-epoxyergostan-3-ol,4,4,14-trimethyl-, acetate was the major compound among all terpenoids. Both acetone and methanol extracts showed excellent antioxidant activity as assessed by DPPH, total antioxidant activity, and FRAP assays. This experimental evidence suggests that G. indica resin is an excellent source of bioactive compounds and can be explored for its medicinal applications.


Assuntos
Antioxidantes , Garcinia , Antioxidantes/química , Extratos Vegetais/química , Metanol , Cromatografia Gasosa-Espectrometria de Massas , Acetona/análise , Compostos Fitoquímicos/química
6.
Environ Sci Pollut Res Int ; 30(16): 46147-46158, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36715795

RESUMO

Petioles of betel leaf (BLP) are the major industrial by-products of betel leaf industries sold at throwaway prices or used as cattle feed. The present work was taken up to evaluate suitable solvent based on yield, antioxidant, and antimicrobial properties to isolate extract of BLP using the Shannon entropy-TOPSIS method. Four solvents were chosen for the extraction process: hexane, toluene + ethanol (2:1), acetone, and ethanol. The findings showed that ethanol-based BLP extract had the highest TPC value, measuring 2193.71 ± 0.17 mg of gallic acid equivalence/g of dry extract, while acetone-based extracts had the highest TFC value, measuring 8.03 mg of quercetin equivalent/g of dry extract. Radical scavenging activities like DPPH (IC50 = 52.44 µg/mL), ABTS (IC50 = 62.41 µg/mL), and FRAP (8.03 mg QE/g of dry extract) were found best for acetone extract. The antibacterial study of the extracts revealed that acetone extract was more sensitive to Gram-positive and Gram-negative bacterial strains followed by ethanol, toluene + ethanol, and hexane extracts. Among five foodborne bacteria, B. subtilis showed the highest susceptibility against all extracts. GC-MS analysis showed that acetoxychavicol acetate (31.27%) (PubChem ID: 119,104), germacrene D (7.24%) (PubChem Id: 531,750), isoxylic acid (22.56%) (PubChem ID: 11,892), and cis-1,2-indandiol (43.92%) (PubChem ID: 20,758) are four major compounds among 22 components. TOPSIS analysis revealed that acetone extract had the highest relative closeness value (0.71) followed by ethanol (0.65), toluene + ethanol (0.53), and hexane (0.32). These results indicate that acetone extract of BLP can be considered an alternative to synthetic active ingredients in the future. These results indicated that TOPSIS method has computational robustness for selecting a solvent comparing yield, antioxidant, and antimicrobial activities of extract of a plant part.


Assuntos
Anti-Infecciosos , Piper betle , Animais , Bovinos , Antioxidantes/química , Piper betle/química , Hexanos , Solventes/química , Acetona/análise , Antibacterianos/análise , Anti-Infecciosos/química , Folhas de Planta/química , Etanol/análise , Tolueno/análise , Extratos Vegetais/química
7.
Molecules ; 27(18)2022 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-36144484

RESUMO

Moringa oleifera Lam (syn. M. ptreygosperma Gaertn.) leaves are globally acclaimed for their nutritional content and mitigation of malnutrition. In most impoverished rural communities including Limpopo, Mpumalanga and KwaZulu Natal of South Africa, powdered leaves of Moringa oleifera are applied as a nutritional supplement for readily available food such as porridge for malnourished children and even breast-feeding mothers. Widely practiced and admired is also the use of the plant seed in the do-it-yourself purification of water by rural South Africans. This study aimed at identifying the chemical and nutritional marker compounds present in South African Moringa oleifera seed oils using high resolution 1-2-dimension gas chromatography in order to give scientific validation to its uses in cosmetics and particularly in culinary practices. Results obtained from two-dimension tandem mass spectrometry chemical signature revealed over 250 compounds, five times more than those reported from one-dimension gas chromatography. Whereas previous reports from gas chromatography-mass spectrometry analysis reported oleic acid (70-78%) as the major compound from oil samples from other countries, M. oleifera seed oil from South Africa is marked by cis-13-octadeaconic acid with 78.62% and 41.9% as the predominant monounsaturated fatty acid in the hexane and dichloromethane extracts respectively. This was followed by cis-vaccenic acid, an isomer of oleic acid at 51% in the acetone extract, 9-octadecanoic acid-(z)-methyl ester at 39.18%, 21.34% and 10.06% in dichloromethane, hexane and acetone extracts respectively. However, a principal component analysis with R2 = 0.98 of the two-dimension tandem mass spectrometry cum chemometric analysis indicated n-hexadecanoic acid, oleic acid, 9-octadecanoic acid-(z)-methyl ester and cis-vaccenic acid with a probability of 0.96, 0.88, 0.80 and 0.79 respectively as the marker compounds that should be used for the quality control of moringa seed oils from South Africa. This study demonstrates that South African Moringa oleifera oils contain C-18 monounsaturated fatty acids similar to oils from Egypt (76.2%), Thailand (71.6%) and Pakistan (78.5%) just to mention but a few. These fatty acids are sunflower and olive oil type-compounds and therefore place moringa seed oil for consideration as a cooking oil amongst its other uses.


Assuntos
Moringa oleifera , Moringa , Acetona/análise , Criança , Ésteres/análise , Ácidos Graxos/análise , Cromatografia Gasosa-Espectrometria de Massas , Hexanos , Humanos , Cloreto de Metileno , Moringa oleifera/química , Ácido Oleico/análise , Azeite de Oliva/análise , Ácido Palmítico/análise , Extratos Vegetais/química , Óleos de Plantas/química , Sementes/química , África do Sul , Ácidos Esteáricos/análise , Água/análise
8.
Appl Biochem Biotechnol ; 194(11): 5083-5099, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35689756

RESUMO

Calycopteris floribunda Lam. is a potent medicinal woody climber that belongs to Combretaceae. This plant is usually found in dry deciduous tropical forests and is used in various medicinal practices like Ayurveda, Unani and Sidda. Whole plant and its different parts like leaves, flowers and stem are used in the treatment of diarrhoea, dysentery, jaundice and malaria. It is also have anthelminthic, anti-inflammatory, antifungal, hepatoprotective and anticancerous activities. Knowing its medicinal properties, the present study is undertaken to investigate the preliminary phytochemical constituents and bioactive compounds of flower extracts by GC-MS. GC-MS analysis of flower extracts revealed the presence of over all 41 compounds, of which, acetone and ethanol extracts showed the presence of 13 compounds each, chloroform extract 8 and petroleum ether extract 7 compounds. Some compounds were common in two and three extracts only. The significant bioactive compounds identified are 1,2-benzenedicarboxylic acid (59.81%) in chloroform extract, triterpene lupeol (34.98%) in ethanol extract, tetratetracontane (26.99%) in petroleum ether extract and gamma sitosterol (22.04%) in acetone extract.


Assuntos
Combretaceae , Plantas Medicinais , Triterpenos , Plantas Medicinais/química , Cromatografia Gasosa-Espectrometria de Massas , Sitosteroides , Antifúngicos , Clorofórmio , Acetona/análise , Extratos Vegetais/química , Combretaceae/química , Folhas de Planta/química , Flores/química , Compostos Fitoquímicos/análise , Anti-Inflamatórios , Etanol , Triterpenos/análise
9.
Molecules ; 27(8)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35458657

RESUMO

Quince (Cydonia oblonga Mill.) is a potential source of polyphenolic compounds related with beneficial biological processes. In this study polyphenols from quince fruit were extracted with aqueous acetone at different ratios. A polyphenol profile was identified and quantified by LC-ESI-QqQ. The antioxidant capacity (ORAC and DPPH) and anti-inflammatory effect (inhibition of COX-2 cyclooxygenase) were evaluated in vitro. The results indicated an effect of the aqueous acetone ratio on the extraction of polyphenolic compounds. The higher extraction yields of polyphenolic compounds were attained with 60-75% aqueous acetone. However, extracts obtained with 85% aqueous acetone promoted higher antioxidant and anti-inflammatory effects. Optimal scaling analysis indicated that hydroxycinnamic acids (quinic and chlorogenic), hydroxybenzoic acids (vanillic and syringic), flavonoids (quercetin and kaempferol), dihydrochalcones (neohesperidin) and flavones (acacetin) are related to the antioxidant activity of quince. While phenolic acids, flavonols (kaempferol-3-O-glucoside and rutin) and flavanols (epicatechin) generated the anti-inflammatory effect by inhibiting 52.3% of the COX-2 enzyme. Therefore, a selective extraction of phenolic mix can reduce oxidative stress or inflammatory processes. This suggests the use of quince as a natural source with significant nutraceutical potential.


Assuntos
Rosaceae , Acetona/análise , Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Ciclo-Oxigenase 2 , Suplementos Nutricionais/análise , Flavonoides/análise , Flavonoides/farmacologia , Frutas/química , Hidroxibenzoatos/análise , Extratos Vegetais/química , Polifenóis/química , Rosaceae/química
10.
J Agric Food Chem ; 68(10): 2906-2916, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-31267749

RESUMO

In this study, we optimized the HCl-butanol-acetone-iron (HBAI) assay for the analysis of B-linked procyanidin (PC) and prodelphinidin (PD) condensed tannins (CTs) by direct analysis of whole tissue and sequential analysis of acetone-water extracts and insoluble residues prepared from forage, woody plant, food, and food byproduct samples. Yields of anthocyanidins (cyanidin and delphinidin) were optimized by heating ≤0.25 mg mL-1 CT standards, 1 mg mL-1 tissue, or 1-2 mg mL-1 acetone-water fractioned tissue for 3 h at 70 °C in medium containing 5% concentrated HCl, 6.7% total water, 50% acetone, 42% n-butanol, and 0.15% ammonium iron(III) sulfate dodecahydrate. Accurate quantitation required CT standards of known purity sourced from the same tissue being analyzed. Both analysis methods provided comparable estimates of total CTs for most PD-rich samples, but only the sequential method gave good recovery and accurate estimates of CTs in most PC-rich samples.


Assuntos
Biflavonoides/análise , Catequina/análise , Técnicas de Química Analítica/métodos , Análise de Alimentos/métodos , Extratos Vegetais/análise , Proantocianidinas/análise , Taninos/análise , 1-Butanol/análise , Acetona/análise , Ácido Clorídrico/química , Ferro/análise
11.
Regul Toxicol Pharmacol ; 107: 104406, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31238087

RESUMO

In this study, 48 herbal based products (41 for the pediatric population) were analyzed for the presence of ethanol and residual solvents. Ethanol was not detected in only 12% of the products designed for infants or toddlers aged under 2, and not quantified in only 5 of 14 'alcohol free' products. Actual content was higher than labeled in six out of 11 samples with specified ethanol quantity. WHO proposed requirement for ethanol content in products intended for use in children under the age of 6 (<0.5%) was not met by as many as 26 samples. Furthermore, calculated blood alcohol levels in children exceeded the relevant toxicological levels for nine samples following a single dose, and for one sample in case of accidental poisoning with the entire package. Regarding the residual solvents, acetone, 1-propanol and 1-butanol were not quantified, 2-propanol was found in two samples in low concentrations, whereas methanol intake via one of the samples exceeded the permitted level for children. The obtained results revealed a significant health concern for the pediatric population due to ethanol intake via herbal based products, calling for the establishment of strict guidelines for ethanol content and labeling.


Assuntos
Acetona/análise , Álcoois/análise , Preparações de Plantas/análise , Solventes/análise , Criança , Pré-Escolar , Qualidade de Produtos para o Consumidor , Humanos , Lactente , Medição de Risco
12.
Forensic Sci Int ; 297: 171-176, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30798102

RESUMO

BACKGROUND: Hair analysis is a suitable way to discriminate between coca chewers and consumers of manufactured cocaine using the coca alkaloids hygrine (HYG) and cuscohygrine (CUS) as markers. In the present preliminary study it was examined whether CUS and HYG can be detected in hair of occasional and moderate coca chewers or coca tea drinkers, whether CUS and HYG appear in hair of PACO consumers (smoking coca paste waste), and whether anhydroecgonine methyl ester (AEME) is a useful cocaine smoking marker in this context. METHOD: Three groups were included: 10 volunteers from Buenos Aires with occasional or moderate chewing of coca leaves or drinking coca tea, 20 Argentinean PACO smokers and 8 German cocaine users. The hair samples (1-4 segments) were analyzed by a validated LC-MS/MS method for cocaine (COC), norcocaine (NC), benzoylecgonine (BE), ecgonine methyl ester (EME), cocaethylene (CE), cinnamoylcocaine (CIN), tropacocaine (TRO), AEME, CUS and HYG. For comparison, eight samples of coca leaves or coca tea were analyzed. RESULTS: Only low concentrations of COC were found in hair of seven occasional users of coca leaves or coca tea (0.010-0.051 ng/mg). For three moderate chewers of coca leaves all compounds were detected including AEME but except TRO. The hair samples of PACO smokers contained much higher concentrations of COC (0.027-341 ng/mg, mean 37.4 ng/mg) and its metabolites. CUS was not found in these samples but traces of HYG were seen in 8 of 37 hair segments. AEME as a marker for coca smoking was detected in hair of 15 smokers. In comparison to COC, the concentrations of EME and CIN were higher for PACO smokers than for German cocaine consumers. AEME (56 ± 20 µg/g) was detected in all coca leave and coca tea samples which explains the detection of this substance in hair of coca chewers. Therefore, its use for differentiation between coca chewers and PACO smokers is limited. CONCLUSION: CUS remains to be the most suitable marker in hair for chewing coca leaves or drinking coca tea more frequently than two times per month since it does not appear in hair of Argentinean PACO smokers and German cocaine users. Contrary to a previous proposal, the ratios CIN/COC and EME/COC appeared not to be applicable as criteria for this purpose because of the higher concentration of these alkaloids in hair of PACO smokers. More research is needed to assess the value of AEME in hair of South American coca leave or cocaine users.


Assuntos
Coca , Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Cabelo/química , Detecção do Abuso de Substâncias/métodos , Acetona/análogos & derivados , Acetona/análise , Adolescente , Adulto , Biomarcadores/análise , Cocaína/análogos & derivados , Cocaína/análise , Feminino , Humanos , Masculino , Mastigação , Pessoa de Meia-Idade , Folhas de Planta , Pirrolidinas/análise , Fumar , Chá , Adulto Jovem
13.
J Sep Sci ; 41(3): 648-656, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29134791

RESUMO

A precise identification method was developed to identify the flavors and fragrances added to tea matrix artificially using gas chromatography with mass spectrometry and gas chromatography with quadrupole time-of-flight mass spectrometry. The proposed method was based on the corresponding "three-column retention indices, two exact mass numbers, one mass spectrum matching degree" database of 40 kinds of common flavors and fragrances. The intraday and the interday relative standard deviation of the retention indices were less than 0.048 and 0.093%, respectively. The accuracy of exact mass was between 0.15 and 6.22 ppm. And the validation of the created database was performed by analyzing the tea samples. Thus, the proposed method is suitable for the precise identification of the flavors and fragrances added to tea matrix artificially without standard substances as a reference.


Assuntos
Aromatizantes/análise , Análise de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Espectrometria de Massas , Perfumes/análise , Chá/química , Acetona/análise , Aromatizantes/química , Hexanos/análise , Perfumes/química , Padrões de Referência , Valores de Referência , Reprodutibilidade dos Testes
14.
Talanta ; 176: 47-51, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28917778

RESUMO

This paper reports a full evaporation (FE) headspace gas chromatographic (HS-GC) method for the determination of the volatile organic compounds (VOCs) in bio-oil (i.e. methanol, ethanol, acetone, acetic acid and furfural). The method uses a 4µL sample of bio-oil in a headspace vial (ca. 20mL). Complete evaporation of the compounds was achieved after seven minutes at 90°C. The method showed good precision and accuracy for methanol, ethanol, acetone and acetic acid. The recovery of furfural was low (74.3%). The results showed that the protocol can be applied for the determination of methanol, ethanol, acetone and acetic acid in bio-oil. Detection limits ranged from 0.13 to 0.16µg. Acetic acid was the dominant analyte in the heavy bio-oil and light bio-oil analysis (113. 3 and 85.1µgmg-1, respectively), followed by methanol, ethanol, and acetone. The polymerisation of furfural was suspected as the cause of its poor quantification.


Assuntos
Eucalyptus , Óleos de Plantas/análise , Polifenóis/análise , Compostos Orgânicos Voláteis/análise , Acetatos/análise , Acetona/análise , Cromatografia Gasosa/métodos , Etanol/análise , Furaldeído/análise , Metanol/análise
15.
Int J Legal Med ; 129(1): 69-84, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25138383

RESUMO

Contrary to the illegal use of any form of manufactured cocaine, chewing of coca leaves and drinking of coca tea are allowed and are very common and socially integrated in several South American countries. Because of this different legal state, an analytical method for discrimination between use of coca leaves and abuse of processed cocaine preparations is required. In this study, the applicability of hair analysis for this purpose was examined. Hair samples from 26 Argentinean coca chewers and 22 German cocaine users were analysed for cocaine (COC), norcocaine (NC), benzoylecgonine (BE), ecgonine methyl ester (EME), cocaethylene (CE), cinnamoylcocaine (CIN), tropacocaine (TRO), cuscohygrine (CUS) and hygrine (HYG) by hydrophilic interaction liquid chromatography (HILIC) in combination with triplequad mass spectrometry (MS/MS) and hybrid quadrupole time-of-flight mass spectrometry (QTOF-MS). The following concentrations (range, median, ng/mg) were determined in hair of the coca chewers: COC 0.085-75.5, 17.0; NC 0.03-1.15, 0.12; BE 0.046-35.5, 6.1; EME 0.014-6.0, 0.66; CE 0.00-13.8, 0.38; CIN 0.005-16.8, 0.79; TRO 0.02-0.16, 0.023; CUS 0.026-26.7, 0.31. In lack of a reference substance, only qualitative data were obtained for HYG, and two metabolites of CUS were detected which were not found in hair of the cocaine users. For interpretation, the concentrations of the metabolites and of the coca alkaloids in relation to cocaine were statistically compared between coca chewers and cocaine users. By analysis of variance (ANOVA) significant differences were found for all analytes (α = 0.000 to 0.030) with the exception of TRO (α = 0.218). The ratios CUS/COC, CIN/COC and EME/COC appeared to be the most suitable criteria for discrimination between both groups with the means and medians 5-fold to 10-fold higher for coca chewers and a low overlap of the ranges between both groups. The same was qualitatively found for HYG. However, these criteria cannot exclude cocaine use in addition to coca chewing. In this regard screening for typical cutting agents can be helpful and led to the detection of levamisole (21×), lidocaine (6×) and paracetamol (3×) in the 22 samples from German cocaine users, whereas no levamisole, lidocaine (3×) and paracetamol (1×) were found in hair from the Argentinean coca chewers. These criteria have to be confirmed for South American cocaine consumers including smokers of coca paste and may be different because of different composition of the drug and other use habits.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Cabelo/química , Mastigação , Folhas de Planta , Chá , Acetaminofen/análise , Acetona/análogos & derivados , Acetona/análise , Adolescente , Adulto , Idoso , Cromatografia Líquida , Coca , Cocaína/análogos & derivados , Cocaína/análise , Contaminação de Medicamentos , Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , Feminino , Toxicologia Forense/métodos , Humanos , Levamisol/análise , Lidocaína/análise , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Pirrolidinas/análise
16.
Food Chem ; 164: 347-54, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24996344

RESUMO

Originally from Asia, Dovyalis hebecarpa is a dark purple/red exotic berry now also produced in Brazil. However, no reports were found in the literature about phenolic extraction or characterisation of this berry. In this study we evaluate the extraction optimisation of anthocyanins and total phenolics in D. hebecarpa berries aiming at the development of a simple and mild analytical technique. Multivariate analysis was used to optimise the extraction variables (ethanol:water:acetone solvent proportions, times, and acid concentrations) at different levels. Acetone/water (20/80 v/v) gave the highest anthocyanin extraction yield, but pure water and different proportions of acetone/water or acetone/ethanol/water (with >50% of water) were also effective. Neither acid concentration nor time had a significant effect on extraction efficiency allowing to fix the recommended parameters at the lowest values tested (0.35% formic acid v/v, and 17.6 min). Under optimised conditions, extraction efficiencies were increased by 31.5% and 11% for anthocyanin and total phenolics, respectively as compared to traditional methods that use more solvent and time. Thus, the optimised methodology increased yields being less hazardous and time consuming than traditional methods. Finally, freeze-dried D. hebecarpa showed high content of target phytochemicals (319 mg/100g and 1,421 mg/100g of total anthocyanin and total phenolic content, respectively).


Assuntos
Frutas/química , Extração Líquido-Líquido/métodos , Extratos Vegetais/química , Polifenóis/isolamento & purificação , Ribes/química , Acetona/análise , Antocianinas/química , Brasil , Etanol/análise , Frutas/crescimento & desenvolvimento , Fenóis/análise , Ribes/crescimento & desenvolvimento , Solventes/química , Sri Lanka , Água/análise
17.
J Chromatogr A ; 1333: 99-105, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24529959

RESUMO

In this work, an ion mobility spectrometer (IMS) with a tritium ionization source on-line coupled to a headspace (HS) autosampler and a multicapillary column (MCC) was evaluated for the monitoring of lipid oxidation products in milk with different flavours (cacao, fruits, cereals and nuts) and linseed oil samples enriched with omega-3 acids. In this combination, the multicapillary column is used as an interface between the HS and the IMS, providing the efficient separation of the volatile compounds. In this way, the proposed method permits the detection of hexanal, 2-butanone, acetone and dimethyl sulfide as representative degradation products. The limits of detection were in the interval 0.3 µg L(-1) (for hexanal in milk) to 3.0 µg L(-1) (for dimethyl sulfide in linseed oil) while the limits of quantification varied between 1.1 µg L(-1) (for hexanal in milk) and 9.6 µg L(-1) (for dimethyl sulfide in linseed oil). The precision of the method was evaluated as relative standard deviation and the values were better than 8% in all cases. The evolution of the volatiles profile during 36 days under different storage conditions (temperature, oxygen and light) demonstrates the capability of the HS-MCC-IMS coupling for the estimation of the degradation of the samples. After the degradation study, it can be concluded that the stability of the milk samples during storage is more affected by the light while temperature was more critical for oil samples.


Assuntos
Análise de Alimentos/métodos , Análise Espectral/métodos , Acetona/análise , Aldeídos/análise , Animais , Butanonas/análise , Ácidos Graxos Ômega-3/química , Íons , Óleo de Semente do Linho/química , Leite/química , Oxirredução , Sulfetos/análise , Volatilização
18.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 36(6): 599-601, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25556730

RESUMO

OBJECTIVE: To explore the usefulness of head-space gas chromatography for the determination of methanol and ethanol in Haikesu I,a raw material of artificial musk. METHODS: The determination was performed on HP-5(30 m×0.53 mm,5 Μm)capillary column with an hydrogen flame ionization detector. The solvent was dimethyl sulfoxide and the internal standard was acetone. The injector temperature and the detector temperature were controlled at 180 ℃ and 250 ℃,respectively. The carrier gas was nitrogen. The containers of head-space injector were preheated at 90 ℃ for 15 minutes. The column temperature was programmed raised,which achieved baseline separation of the components. RESULTS: The results showed a good linear relationship for methanol and ethanol in their linearity range;and the limit of detection was 0.8 and 1.0 Μg/ml,respectively. The precision and average recoveries were satisfactory. CONCLUSION: The head-space gas chromatography is simple,rapid,and precise technique for the measurement of residual solvents in Haikesu I.


Assuntos
Cromatografia Gasosa , Medicamentos de Ervas Chinesas/química , Solventes/análise , Acetona/análise , Etanol/análise , Ionização de Chama , Metanol/análise
19.
Zhong Yao Cai ; 36(6): 929-33, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-24380278

RESUMO

OBJECTIVE: To study the chemical constituents of the volatile oil from Aquilariae Lignum Resinatum by the technical of Aquilariae Lignum Resinatum making incense. METHODS: Volatile Oil Extraction method was used to extract volatile constituents from different batches of Aquilariae Lignum Resinatum, and the composition was analyzed by GC-MS. RESULTS: 56 chemical constituents were extracted from Aquilariae Lignum Resinatum, 36 constituents of them were reported for the first time;The chemical constituents were slightly different among three batches of Aquilariae Lignum Resinatum, but all the volatile oils were mainly composed of sesquiterpenes and aromatic composition; And all three batches of samples contained characteristic active ingredients including Aloes spiral alcohol, Benzyl acetone and the contents of them had increasing trend with the Aquilariae Lignum Resinatum concreting period growing. CONCLUSION: Chemical constituents extracted from the Aquilariae Lignum Resinatum concreting by new method were similar with natural Aquilariae Lignum Resinatum, and in a relatively short period of time, can produce relatively high content of effective and characteristic components.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Óleos Voláteis/análise , Óleos de Plantas/análise , Sesquiterpenos/análise , Thymelaeaceae/química , Acetona/análogos & derivados , Acetona/análise , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Controle de Qualidade , Tecnologia Farmacêutica/métodos , Terpenos/análise
20.
Pharm Biol ; 49(6): 569-76, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21385091

RESUMO

CONTEXT: Bombax malabaricum DC. (Bombacaceae) is a traditional Chinese herbal medicine used for the treatment of inflammatory conditions, diarrhea, fever, chronic inflammation, catarrhal affection, and as a diuretic. However, little information is available about its antioxidative activity. OBJECTIVE: Water, 50% ethanol, and 80% acetone extracts from flowers of B. malabaricum were investigated for their in vitro antioxidant activity in this article for the first time. Then the relationships between antioxidant activity measured by different methods and total phenolic content (TPC) and total flavonoid content (TFC) were established. MATERIALS AND METHODS: The antioxidant activities of extracts from B. malabaricum flower were investigated including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, oxygen radical absorbance capacity (ORAC), reducing power, and inhibition on phosphatidylcholine liposome peroxidation. RESULTS: Results showed that all the extracts possessed remarkable antioxidant capacity compared with ascorbic or gallic acids. Total antioxidant activities evaluated by ORAC assay of different extracts ranged from 700.03 to 1482.46 µmol Trolox equivalents/g. The highest TPC of 130.38 mg gallic acid equivalents (GAE)/g was observed in 80% acetone extract, whereas the lowest TPC of 57.09 mg GAE/g was obtained in the water extract. Furthermore, TFC exhibited significant (P < 0.05) positive correlations with DPPH radical-scavenging activity, ORAC, and reducing power. DISCUSSION AND CONCLUSION: These findings demonstrate that the flowers of B. malabaricum have excellent antioxidant activities and thus might be a potential source of natural antioxidants.


Assuntos
Antioxidantes/farmacologia , Bombax/química , Flores/química , Extratos Vegetais/farmacologia , Acetona/análise , Antocianinas/química , Antioxidantes/química , Ácido Ascórbico/farmacologia , Colorimetria/métodos , Avaliação Pré-Clínica de Medicamentos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Etanol/análise , Flavonoides/química , Flavonoides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Ácido Gálico/farmacologia , Técnicas In Vitro , Peroxidação de Lipídeos/efeitos dos fármacos , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/química , Água/análise
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